Rating: 

The biggest problem with UNIX is not a problem with it at all, it's a problem that no one who doesn't think they can understand it ever will. The commands are arbitrary, mistakes are easy, documentation is often faulty ( the man page is for one version of grep, and a different one is in a user's path ), and exercising the system requires a great deal of imagination from the command line.

Of course we have GUIs now, but the bottom line is to really understand 'NIX you need to understand the command line. This book clears the cobwebs away. Everytime I have had some poor soul thrust at me by a manager to unwillingly "learn UNIX", they seem bent on deciding UNIX is too fustrating, complex, or dated to be worth learning. In response have given them this book instead of telling them about man -k. Every one of them then decided they wanted to know more, all of them ended up sysadmins on some level.

I cannot recommend this book more strongly.